Apparatus for cooling and scrubbing gases



A. M. HUNT AND D. E. FOGG. A APRAHAIUS FOB cooLING AND sCRUBlNG GASES.

.APPLICATION FILED MAY 25, 1914.

1,327,599, v Patented Jan. 6.1920.

L SHEETS-SHEET I. 259,1. y I

VVITNESSES:

v INYEN'LORS andrew MEM?, Ja/zaidjlog A. M. HUNT AND D. E. FOGG.. APPARATUS Fon cooUNG AND scRulNG .GAsEs. APPLICATION FILED M/IY25, 1914.

2 SHEETS-SHEET 2.

E? wfmf Patented J an. 6, 1920.

' water for cooling the UNTED STATES rar-ENT onirica.

ANDREW M. HUNT, 0F BERKELEY, AND DONALD E. FOGG, 0F OAKLAND,` CALEORNIA.

APPARATUS FOB COOLING AND SCRUBBING GASES.

Patented Jan. 6, 1920.

Application filed May 25, 1914. Serial No. 840,756.

This invention relates to a process for.

cooling hot gases and cleansing hot gases carrying solid or liquid particles or condensable vapors and relates also to a self contained device for the application of this process.

The process involves generallyv the coolingand scrubbing of hot gases carrying solid or liquid particles or condensable vapors which consists in passing them through an inclosed space where they are showered with a liquid. Said inclosed space contains a set of pipes through which cooling water circulates. The scrubbing liquid performs a double function, it first knocks ldown any solid or liquid-particles and being broken into a fine spray by the current of the gases presents a greatly increased surface for absorption of heat from the gases, and thisfine spray then comes in contact with the cooled pipes, gives up its heat and is blown off to pick up more heat from the gas. ln other words, the mist of the scrubbing liquid plays the part of Aan abstractor of heat from the gas, which it conveys to and delivers up tothe cooling pipes. y

Figure v1 of the drawing is a vertical section of an apparatus suitable for practising the process. i Fig. 2 is a section on lineX-eX of Fig-1. A indicates a tower or other inclosed space havingv an inlet 2 for the hot gases at .some point adjacent to but preferably above the bottom of the tower; the vcooled scrubbed gases issuing through the stack 3. 4 is a header or'water column arranged centrally within the tower and constitutes a reservoir to contain cold circulated in coils 5, preferably of lead arranged in pancakes in the annular space 6 between the header 4 andthe walls of the above andbelow the gas If desired the space in the header inlet 2 may bedividedby a partition' 7 vforming an upper tower.

water chamber 8, with which the banks of pancake coils 5 connect, and a lower water from the top of the, tower gases, which water issuits to .be accomplished.

space or reservoir 9 with which the banks of pancake coils 5 below the gas inlet 2 connect; the water in the compartment 9' usually being colder than that within the compartments 8.

Any appropriate form of construction may be employed for connecting the coils 5-5 with the headert. Preferably though, the header 4 is in shape in cross-section of that of a snail, as shown in Fig. 2, with the pipes 5 5 heading through the vertical radial wall lOwith each pipe provided with a regulating valve 1l by which the quantity of water passing through the coils 5-5 may be regulated according to the temperature at which 1t 1s desired to keep them.

pipes after taking their water from the header delivered 1t into a stand pipe 12, which discharges into a sump 13 and after cooling is delivered' by appropriate. means, as a centrifugal pump 14, by separate conL duits 15-16 leading respectively to the compartments 8-9, so that the cooling water is continually circulated, entering as cold water in the compartments v8 4); discharging as hot water through the header 12, cooled and thence re-circulated.

As before stated, there are two series of banks of coils'5-5, the former above the gas inlet 2, and therl by arranged directly in the path of the ascending gases; vand the other series, 5' being below the inlet 2, and not, .to any a preciable degree, coming in contact with tliie gases passing through the apparatus. The function of these two series or sets of coils will be referred to later.

Arranged in theupper part of the appara-l tus, so as to spray a suitable liquid downwardly upon all the pipes 5-5, is a ysuitable spraying device, such as the perforated pipe 17, which is' connected by a pipe 118 with the centrifugal pump 19, which latter has its suction side connected with the bottom of the towerA by the pipe 20, so that a continuous circulation of 4spraying liquid may bekept up through the apparatus; the

'character' of this scrubbing liquid varying with the different gases handled and the re- Thescrubbing liquid is broken up into a inist by the velocity of the gas and exposes an enormous area to the gas or heat absorp- Y:tio-Fri by the scrubbing liquid. The scrubbing liquid, in its misted form, then impinges against the lead pipes'5, condenses thereon, and drips off to be again disrupted. The heat transfer through the lead coil is really from liquid on the outside to liquid on the inside instead of from gas on the outside to liquid on the inside.

In such an inclosed'space or tower in actual service, the lower pancake coils 5 closest to the inlet 2 of hot gases absorb a great amount of heat and the absorption ot' each succeeding set of coils decreases as the temperature of the gases falls. The same thing is true of the lower sets of cooling coils 5 below the hot gas inlet the function of which sets of coils is solely to cool the hot liquid formed by condensation ot'- spray after same has completely passed through the hot gases. tion of variable heat absorption by the separate sets of coils, the amount of cooling liquid passed through each `individual set of cooling coils is carefully regulated and in this manner any temperature of exit gases desired down to the temperature of the cooling water itself may be maintained and closely controlled.

The amount of liquid actually in contact with the gases is small, and being constantly recirculated, it is a comparatively simple matter to settle out the suspended solids and save them if desirable.

A sutlicient quantity of the liquid is maintained in circulation through the inclosed space to absorb the entire quantity of heat Vwhich is to be removed without reference to the cooling action of the pipes upon the gas direct; the function of the pipes being primarily to cool the liquid spray.

Having thus described our invention what we `claim and desire to secure by Letters Patent is* 1. An apparatus for cooling and scrubbing hot gases, 'consisting of a tower having a gas inlet at one side and above the bottom thereof, and a gas out-let at the top, lbanks of cooling coils in the tower above and below the gas inlet, means for spraylng 'a liquid on the pipes and counter to the currents of gases, a header inthe tower with which the cooling pipes connect, and means for maintaining a constant circulation, with` To meet this conditom, a gas outlet at its intermittent cooling of a second liquid, through said header and pipes.

2. An apparatus for cooling and scrubbing hot gases, consisting of a tower having a gas inlet and a gas outlet, a set of cooling coils above thev gas inlet in the path of the hot gases, the path of the hot gases and upon said coils, and ymeans including' a set of cooling coils below the gas inlet and out of the path of the entering hot gases for cooling the spraying liquid, a header in the tower with which the cooling pipes connect, means for maintaining a constant circulation of a second liquid, with intermittent cooling thereof, through said header and pipes, and means for returning the cooled spraying liquid again to the top of the tower for re-use.

3. An apparatus for cooling and scrubbing hot gases, comprising a chamber having a gas inlet intermediate its top and bottop, banks of cooling coils in the tower above and below the gas inlet, means for spraying a liquid over `said coils, a header with which said cooling coils connect, said header comprising two portions feeding the coils above and below the gas inlet respectively, and means for circulating cooling liquid through said header and" coils.

means for spraying a liquid intok 4. An apparatus for cooling and scrubi bing hot gases, comprising a tower having a gas inlet intermediate its top and bottom, a gas outlet above said gas inlet, a series ot' distinct cooling coils -above and below the' gas inlet, means for spraying a liquid over said cooling coils, a header with which said coi/ls connect, means for circulating cooling liquid through said coils and means outside vsaid tower for independently regulating the flow of liquid throughv each coil, whereby the coils may be maintained at diil'erent temperatures.

I n testimony whereof set our hands in the we have hereunto scribing witnesses.`

ANDREW-M. HUNT. DONALD E. FOGfG.` Witnesses: I JAMES M. HUNT,

A. M. COLE. y

presence ofjtwo Sub- 

